3D Knits
Spacer fabric stiffness lives in the fourth power of the monofilament diameter and the square of the thickness. Small changes to either are not small.
— kPa
Pressure at which the spacer filaments begin to buckle
Euler buckling describes onset only; past it the filaments carry load in a nonlinear post-buckled state, which is where a real cushioning curve lives. Treat this as the threshold, not the whole response, and confirm on a compression tester.
Spacer Fabric Thickness & Compression Predictor — free, with the formula and a worked example, at Textile School.